An inkjet printer that uses a UV curable ink is known in the art.
Ink dots that constitute images or characters that are printed on a surface of a recording medium by the inkjet printer that uses the UV curable ink are deposited on the surface of the recording medium in a bulging state in a semispherical shape or a substantially semispherical shape. Due to such a shape of the dots, a light is diffusely reflected by the surface, and the surface of the printed images or characters lacks glossiness. As a result, a quality of an image degrades.
To enhance the glossiness of the surface of the printed images and/or characters by preventing diffused reflection of the light from the surface of the images and/or characters, a technology is disclosed in Patent Document 1 in which a transparent or a semitransparent clear coat layer is formed on the ink dots that constitute the images and/or characters.
To prevent mixing of a clear ink or an opaque ink, such as a white ink and a metallic ink, used in such an over coat with other colored inks such as YMCK, overprinting, that is, reprinting is generally performed after the colored ink is printed.
However, if the colored ink is in a completely cured state at the time of performing overprinting on a colored ink print using a UV printer, the ink used in the overprinting repels the colored ink. This leads to reduction in a bonding strength between both the inks, or the ink used in the overprinting coagulates on the colored ink in the form of droplets, forming what is called beading, and printing cannot be performed uniformly.